package com.sky.aspect;


import com.sky.annotation.AutoFill;
import com.sky.constant.AutoFillConstant;
import com.sky.context.BaseContext;
import com.sky.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;
import java.time.LocalDateTime;

//自定义切面，实现自动填充
@Aspect
@Component
@Slf4j
public class AutoFillAspect {
    //切入点
    @Pointcut("execution(* com.sky.mapper.*.*(..))&&@annotation(com.sky.annotation.AutoFill)")
    public void autoFillPointCut(){

    }

    //前置通知，在通知中进行共字段的复制
    @Before("autoFillPointCut()")
    public void autoFill(JoinPoint joinPoint)  {
        log.info("开始进行公共字段自动填充...");

        //获取当前被拦截的方法上的数据库操作的类型
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();//方法签名对象
        AutoFill autoFill = signature.getMethod().getAnnotation(AutoFill.class);//获得方法上的注解对象
        OperationType operationType = autoFill.value();//获得数据库操作类型

        //获取当前被拦截的方法的参数--实体对象
        Object[] args = joinPoint.getArgs();
        if(args == null | args.length == 0){
            return;
        }
        Object entity = args[0];

        //准备赋值的数据
        LocalDateTime now = LocalDateTime.now();
        Long currentId = BaseContext.getCurrentId();

        //为实体对象的公共属性来统一赋值--反射
        if(operationType == OperationType.INSERT){
            //为4个公共字段赋值
            try {
                Method setCreateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME, LocalDateTime.class);
                Method setCreateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_USER, Long.class);
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, LocalDateTime.class);

                //通过反射为对象的属性进行赋值
                setCreateTime.invoke(entity, now);
                setCreateUser.invoke(entity, currentId);
                setUpdateTime.invoke(entity, now);
                setUpdateUser.invoke(entity, currentId);

            } catch (Exception e) {
                throw new RuntimeException(e);
            }

        }else if(operationType == OperationType.UPDATE){
            //为两个公共字段赋值
            try {
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, LocalDateTime.class);

                //通过反射为对象的属性进行赋值
                setUpdateTime.invoke(entity, now);
                setUpdateUser.invoke(entity, currentId);

            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}
